Chair-iron



0. a. COLLIER.

CHAIR IRON. APPLICATION FILED AUG-l9, 1920.

Patented Dec. 6, 1921.

NITED are DAVID It. COLLIER, OF GARDNER, MASSACHUSETTS, ASSIGNOR T0COLLIER- KEYVJ COMPANY, MA$SACHUSIETT&

(Ell: GARDNER, MJWSAEHUEETTS, A UORPGRATIDN 01* otters-inert.

Specification of Letters Eatent.

Patented Dec. 6, 1921 Application filed August 19, 1920. Serial No.4%,602.

metal rolled into tubular form. An object of the present invention is toso construct the tubular spindle that the parts thereof heretoforesubjected to the greatest strain will be strengthened and also more orless relieved of such strain. Another object of the invention is tosecure the head to the spindle without weakening the spindleintermediate of its ends.

In the embodiment of my invention shown on the drawings, Figure 1 is aperspective view of the tubular spindle with a head attached thereto.

Fig. 2 is a vertical section through the head and the upper end of thetube showing the connection between the parts and the re intorce withinthe spindle.

Fig. 8 is a perspective view on an enlarged. scale of the reinforcingtube.

Fig. 4 is a section taken on line 1-4 Fig. 3, looking in the directionof the arrows.

in the followino description only such parts of the chair lrons will beset forth as are pertinent to the present invention. F or the disclosureof the parts to which the parts herein disclosed relate, reference maybe made to my Letters Patent No. 1,287,640 dated December 17, 1918,showing a chair iron on which the present invention is an improvement.

In the drawings, 10 designates a spindle to be used with swivel chairsor the like. The spindle is of tubular form made from a blank of sheetmetal formed with diagonally extending corrugations at one end and anoutstanding rib adjacent the other end, the corrugations providingthreads 11 and the rib providing a circumferential bead 12, when theblank is rolled into tubular form.

Between its ends the spindle is provided with a longitudinal slot 13termed by cutting away the adjacent edges oi": the tube and into thisslot certain locking devices not shown and not a part of the presentinvention, adapted to project to hold the spindle against rotation.

Secured to the. tube at its upper end is a head member which comprisesupper and lower plates 14 and 15 formed with central apertures 16 and 17to receive the end of the spindle. The lower plate 15 is provided withupstanding arms 18 to constitute a yoke and the upper plate is formedwith downwardly projecting flanges 19 secured to arms 18 by rivets 20 orother suitable fastening means.

The upper plate 14 is held rigidly attached to the spindle by the bead12 and a flange 21 between which it is gripped; the bead 12 beingpreferably formed as set forth above and the flange 21 being preferablyformed by peening over the upper end of the spindle after the plate 12has been placed on the bead.

The weight of the chair seat rests on the head 12 and the lower plateacts to steady the upper plate and to prevent turning action thereofrelative to the spindle. T he location 01 the head 12 adjacent the upperend of the spindle as shown in the drawings, instead of at a point lowerdown, greatly lessens the chance of the spindle breaking in the plane ofsaid head due to any weakening ot' the metal that might occur in formingthe bead or leverage between the bead and the upper end of the spindle.

The spindle is further strengthened against fracture or bending in thisregion by a tube 22 driven into the spindle from the upper end. The tube22 is formed of sheet metal rolled into cylindrical form with itsadjacent edges slightly spaced apart. The tube is normally somewhatgreater in diameter than the bore of the spindle and when driven intoplace contracts and forms a tight fit within the bore whereby it is heldfirmly in place. The tube 22 may be formed at its lower end with agroove extending longitudinally of the spindle and located opposite theslot 13 to avoid interference with a locking device projecting into theslot. By the above construction the likelihood of the spindle snappingoil or bending, due to strain on the spindle when the chair seat istilted, is very much diminished and the life of the spindle is very muchprolonged.

In assembling the parts the plate 14' is slipped onto the spindle fromthe upper end and the plate 15 is slipped on from the lower end and theparts are riveted together.

The tube 22 is then forced into the bore of the spindle and the end ofthe spindle peened down to form; the-flange 21 to hold the plate place.

What I claim is:

1. A spindle for swivel chairs and the like, formed of sheet metalrolled into the form of a tube, a head connected with said tube, saidhead comprising parallel upper and lower plates having apertures throughwhich the spindle projects, a bead and a flange "formed at the upper endof the spindle between'which the upper plate of the head is secured anda reinforcing tube fitting tightly within the bore of the spindle, andlocated in the zones of the head.

2. A spindle for swivel chairs and the like, said spindle comprising asheet metal tube, a head attached thereto at the upper end, a reinforcefor said tube consisting of a sheet metal tube having a tight fit withthe bore of the spindle at the portion to which the head is attached.

3. A spindle for swivel chairs formed of sheet metal bent intocylindrical form, and having a longitudinal locking slot and a tubelocated Within the spindle and having a groove coinciding with saidslot.

4:. A spindle for swivel chairs, formed of corrugated sheet metal bentinto cylindrical form to provide a threaded tube, and a reinforcing tubewedged into the tube, in combinationwith a head secured to said spindleandrloeated between the upper and lower ends of said reinforcing tube.

In testimony whereof I have afiixed my signature.

DAVID R. COLLIER.

